Process for preparing detergent compositions

ABSTRACT

The invention provides a process of preparing a substantially non-irritant, essentially tertiary amine-free detergent mixture comprising as the active constituents a quaternized tertiary amine and the corresponding tertiary amine N-oxide, in which process a tertiary amine is reacted with a quaternizing agent, to produce a mixture of the free tertiary amine and the quaternized tertiary amine, and this mixture is then subjected to oxidation, thereby converting the free tertiary amine to the amine oxide, and giving the required essentially tertiary amine-free detergent composition.

United States Patent [191 Bloch et al. June 25, 1974 PROCESS FOR PREPARING DETERGENT [56] References Cited COMPOSITIONS UNITED STATES PATENTS [75] Inventors: Michael Bloch, Salmuenster, 3,689,470 9/1972 Shachat et al. -260/501.l3

Germany; Adolph Koebner, Cumberland, England Primary Examiner-Mayer Weinblatt 73 Assignee: Rewo Chemische Fabrik G.m.b.H. Rllms Steinau, Kreis Schluechtem,

[22] Filed. Dec 21 1971 The invention provides a process of preparing a substantially non-irritant, essentially tertiary amine-free [21] Appl. No.: 210,545 detergent mixture comprising as the active constituents a quatemized tertiary amine and the correspond- [30] Foreign Application Priority Data ing tertiary amine N-oxide, in which process a tertiary amine is reacted with a quatemizing agent, to produce Dec. 23, 1970 Germany 2063422 a mixture of the free tertiary amine and the quatep nized tertiary amine, and this mixture is then sub- [52] Cl 252/547 5 8 g g' jected to oxidation, thereby converting the free ter- 1 Int Cl /50 C14! & tiary amine to the amine oxide, and giving the re- 0 n s n [58] Field of Search. 260/567.6 M, 501.12, 501.13, 308mm y y g 5 Claims, No Drawings BACKGROUND OF THE INVENTION This invention relates to a process for the preparation of detergent compositions which have a low content both of electrolytes and unreacted tertiary amine.

It is known that both straight-chain aliphatic and cycloaliphatic tertiary amines may be converted to surface active agents by quatemizing them with halogensubstituted organic carboxylic acids, with halogensubstituted organic sulfonic acids, or with sultones. The resulting quaternary derivatives are surface active agents with useful detergent properties, and are in general kind to the skin and to the eyes. These derivatives are also easily biodegradable, and are extremely versatile products from the formulators point of view in that they are compatible with, and thus may be mixed with, both anionic and cationic surface active agents.

However, the quatemization process employed does not proceed quantitatively when the reactants are used in stoichiometric proportions and according to the recommended procedures of the prior art. Even under ideal conditions for the quatemization, hydrolysis of the halogenated acids takes place to some extent, producing, in the presence of alkali, salts of hydroxy acids and inorganic halide salts, and a significant amount of the tertiary amine remains unquaternized.

In order to obtain a high degree of conversion of the tertiary amine to the quaternized derivative it has been necessary to use a substantial excess of the halogensubstitut'ed acids. Unfortunately, as a consequence the finished product in addition to the desired quaternized derivative then contains a substantial amount of unused quatemizing agent and its breakdown products.

The following Table shows the percentage of a particular tertiary amine (dimethyl-lauryl-amine) converted to the quaternized derivative (the betaine) using different molecular proportions of a particular quaternizing agent (monochloroacetic acid).

Proportion by weight of tertiary amine converted to betaine No. of mols of monochloroacetic acid used per mol of tertiary amine It will be seen that the use of excess tertiary amine resulted in practically all the monochloroacetic acid being used up in the reaction. As a consequence, the finished product contained only very small amounts of the hydroxy acid salts or inorganic halides derived from the break-up of unreacted quatemizing agent. However, in such cases the finished product of course contained a substantial amount of unquaternized tertiary amine.

It will also be seen that in order to quatemize 90 percent of the tertiary amine it was necessary to employ 1.6 gram-mols of monochloroacetic acid for every gram-mol of tertiary amine and in fact, to quatemize something approaching percent of the tertiary amine, about three times the stoichiometric amount of quatemizing agent has to be used (a vast excess). The use of such an excess naturally means that the product contains very large quantities of quatemizing agent break-down products.

'It is in practice most undesirable to have unquatemized tertiary amine remaining as an impurity in the finished product, as the former is irritant to the skin and eyes (a fact of particular significance because the quaternized products are in general mild to the skin, and as such many of them are eminently suitable for use in preparations for washing the skin and hair). However it will be seen from the foregoing that in order to avoid having residual unquaternized tertiary amine in the product it is necessary to resort to using a large excess of quatemizing agent resulting, when alkali has been used in the process, in the presence of substantial amounts of halides and salts of organic hydroxy acids in the finished product. These halides and salts are also undesirable, although for different reasons. Thus, the presence of these substances in the finished product can cause difficulties when the quaternized derivatives are mixed with other surfactants, and the salt content may seriously raise the cloud point of a liquid aqueous preparation, meaning that the mixture may become turbid in cold weather (indeed, in some cases the salt content may lead to salting out" effects, and separation of the mixture into phases may occur on storage).

lt will be clear that the state of the art at the moment is not particularly satisfactory, and accordingly we have attempted to find a process for the preparation of products containing surface active quaternized tertiary amines (betaines) but containing in addition to the desired quaternized product e only small amounts of electrolytes and only an extremely low content of unquaternized tertiary amine. ,The present invention provides such a process.

We have discovered that the not inconsiderable problems posed by the procedures adopted in the past may be dealt with simply, and with advantage, by reacting the complete mixture formed when quatemizing (with such an amount of quatemizing agent as leaves some tertiary amine unquaternized) with an oxidizing agent so as to convert all, or substantially all, of the residual tertiary amine into the corresponding amine oxide.

The amine oxide so formed is skin-friendly (unlike the amine from which it is derived), and has the great advantage that not only is it compatible with the betaine material, but also it enhances the detergent and surface-active properties of the latter.

SUMMARY OF THE INVENTION This invention provides a process for the preparation of a detergent composition mild to the skin and eyes, consisting essentially of a quaternized tertiary amine and the amine oxide derived from the tertiary amine, and substantially without any free tertiary amine content, wherein:

a. a tertiary amine (wherein at least one of the substituent groups contains from 8 to 22 carbon atoms in an unbroken chain, and no two of the substituent groups contain more than 36 carbon atoms in unbroken chains) is reacted with a mono-halogensubstituted organic acid derivative selected from the group consisting of mono-halogen-substituted organic carboxylic acids, mono-halogensubstituted organic sulfonic acids, and alkali-metal, magnesium, calcium, aluminum and zinc salts of these acids, and mixtures thereof, to form a mixture of the free tertiary amine and the corresponding quatemized tertiary amine; and

b. the thus-formed mixture is then subjected to the action of an oxidizing agent selected from the group consisting of hydrogen peroxide, organic peroxides, per-acids, alkali-metal salts of per-acids, and ozone, to form the desired mixture of quaternized tertiary amine and amine oxide.

It will be apparent that the process of the inventio prepares a mixture of quatemized and unquaternized tertiary amine by reacting a tertiary amine with a quaternizing agent (preferably in such amounts as will result in very little excess of quaternizing agent remaining unreacted), and the undesirable residual tertiary amine that this product contains is then converted to the corresponding N-oxide using an oxidizing agent (for preference hydrogen peroxide), thereby obtaining a composition having valuable cleaning properties to which the N-oxide contributes, the composition being substantially milder to the skin than would be the corresponding composition containing tertiary amine instead of amine oxide.

DETAILED DESCRIPTION OF THE INVENTION The tertiary amines which may act as the starting materials for the process of this invention may be selected from a very wide class. Such compounds fall broadly into three main categories, these being long chain, tertiary amine compounds of the formula I, long chain tertiary amine heterocyclic compounds of the formula II and long chain tertiary amine heterocyclic compounds of the formula III.

Rr-N

R 9 R Ro N QRB In these formulae, the various substitutents are defined as follows: R and R are selected from the group consisting of aliphatic radicals and mixed aliphatic- [aromatic radicals containing at least one aliphatic part and at least one aromatic part, said aliphatic and mixed aliphatic/aromatic radicals being of the group consisting of hydrocarbon radicals having from 1 to 22 carbon atoms, hydroxy substituted radicals containing from 1 to 22 carbon atoms and from 1 to 6 non-phenolic hy-- bon atoms, 8 to 22 of which are present in l to 2 unbroken chains, each of which contains from 8 to 22 carbon atoms in a sequence unbroken by other non-carbon atoms, the remaining carbon atoms present being a number selected from the group consisting of zero and integers from 1 to 28 are present in carbon chains all of which contain from 1 to 4 carbon atoms in a sequence unbroken by other non-carbon atoms; 1

R is selected from the group consisting of alkyl radicals containing from I to 4 carbon atoms and the radical (C I-I O) I-I where m is an integer from 1 to 12; R R R and R are chains of groups each selected from the group consisting of S, O, -NR- 10" =N '9 ll 9 CR12= CH2"'"7 where X X X X X X X X X are chains of radicals each selected from the group consisting of -S'-, O NR14, =CH-', CH=, =CR15'-", CR -CI-I -CHR, where one of R R R R R R R R and R is R, another of these is selected from the group comprising R and R and all the remainder are R Amongst the tertiary amines falling within formula II or III is the particularly preferred sub-group of imidazoline derivatives of the formula (wherein R is selected from the groups consisting of unsubstituted, monohydroxy-substituted and dihydroxy-substituted hydrocarbon radicals all containing from 7 to 21 carbon atoms; and R is the hydroxy alkyl radical C H OH where n is an integer from 2 to 4).

Examples of imidazoline derivatives of formula IV particularly suitable for use in the process of the invention are those where R is a 2-hydroxy-ethyl radical and R is one of the following groups:

Examples of further particularly suitable inidazoline derivatives are those wherein R has any of the specific meanings given above, but wherein R represents either the 4-hydroxy-n-butyl group or the 2-hydroxy-npropyl group.

The above derivatives may be prepared in the man ner described in US. Pat. No. 2,267,965 (which refers to the compounds as glyoxalidines). The above exemplified imidazoline derivatives are those which can be derived from naturally occurring fatty acids or products derived from them. Examples of other imidazoline derivatives suitable for use in the process of the invention are those which may be obtained by reacting synthetic fatty acids containing from 8 to 22 carbon atoms, whether these acids contain an even number of carbon atoms like the common naturally occurring fatty acids, or an odd number of carbon atoms, with an amino ethy ethanolamine (i.e., hydroxyethyl ethylene diamine) or N-B-hydroxypropyl propylene diamine in the manner of US. Pat. No. 2,267,965 for the reaction of fatty acids with such polyamines. Mixtures of derivatives are suitable provided the individual derivatives are suitable, and, indeed, frequently the mixture of imidazoline derivatives which is obtainable by reacting mixtures of fatty acids with the approprite polyamine will be particularly suitable. Examples of such mixtures of imidazoline derivatives are those obtainable by reacting amino ethy ethanolamine or N-fl-hydroxypropyl propylene diamine in the manner of US. Pat. No. 2,267,965 with any of the mixtures of fatty acids derived from the following materials; coconut oil, palmkernel oil, groundnut oil, olive oil, cottonseed oil, sunflower oil, safflower oil, teaseed oil, palmoil, linseed oil, soyabean oil, sperm oil, castor oil, tallow, and fish oil; and mixtures of any of the above fatty acids just detailed which have been partially or fully hydrogenated, and also mixtures of fatty acids obtainable synthetically, where the chain lengths of the synthetic fatty acids are such that all the imidazoline derivatives produced from the mixture fall within the scope of the formula given hereinabove. The mixture of fatty acids derived from coconut oil (after removal of the C C acids) is especially suitable.

Naturally, the actual process for preparing these imidazoline derivatives may be carried out under suitable conditions using the appropriate fatty acid esters and fatty acid chlorides as well as or instead of the fatty acids themselves. I

Various other specific tertiary amines falling within formulae I, II and III are as follows:

Compounds within formula I 26) r M 0. 11. c o.NH.cH,--N cm o r-r.cowmoouncnQ-mcm all Compounds within formula II H W-N Many of the tertiary amines of formulae, I, II or 111 are referred to in Chapter 7, pages 151 201 of Surface Active Agents by Schwartz and Perry, 1949 edition, or in Chapter 3, pages 103 l 19 of Surface Active Agents and Detergents, Vol. II, by Schwartz, Perry and Birch. These chapters relate to cationic surface active agents. Others of these compounds are referred to in chapter 9, pages 218 228 of Surface Active Agents, 1949 edition, end in pages 142 143 of Surface Active Agents and Detergents, Vol. II. In many instances the method of preparation of the derivatives is indicated, and in most such instances references are given to more detailed information concerning their manufacture. In some cases, the actual examplified derivatives are variants of derivatives referred to in the works just mentioned, and it is believed, in such cases, that anyone skilled in the art will be able to prepare the variant without difficulty on the basis of the information that can be obtained in this way.

Preferred quaternizing agents for use in the first stage reaction of the process of this invention are those halogenated derivatives falling within the formula C H ,t (OH),,(Z)X, (wherein m is an integer from 1 to 3; p is selected from the group consisting of zero and integers from 1 to the value of m; Z is selected from the group consisting of Cl, Br, and I; and X is selected from the group consisting of SO H and COOH) and the sodium, potassium, lithium, magnesium, calcium, aluminum and zinc salts thereof.

The preferred halogenated derivatives falling within the above definition are acids wherein p is selected from the group consisting of 0 and 1, and the sodium and potassium salts of these acids.

Specific preferred halogenated derivatives are monochloroacetic acid, a-chloropropionic acid, ,B-chloropropionic acid, a-bromopropionic acid, monoiodoacetic acid and a a-chloro-fl-hydroxypropionic acid, and B-chloroethane sulfonic acid, a-chloro-ethane sulfonic acid, B-bromo-ethane sulfonic acid, oz-hydroxy-l3-. chloro-ethane sulfonic acid, and the sodium and potassium salts of all these acids.

The reaction between the tertiary amine and the quaternizing agent in the first stage of the process of 9 the invention is conveniently carried out at a temperature of from 20 to 95 C, preferably from 40 to 60 C, the proportion of quatemizing agent to tertiary amine varying from 0.1 Kg mols to 3.0 Kg mols of quaternizing agent for each 1 Kg mol of tertiary amine, and varying preferably from 0.3 Kg mol to 0.9 Kg mol of quaternizing agent for each 1 Kg mol of tertiary amine. The reaction is normally carried out under alkaline conditions, and where the quaternizing agent is a salt of a halogenated organic acid, or where the agent is the acid itself, but less than 1 Kg mol thereof is used for each 1 Kg mol of the tertiary amine, the reaction mixture will itself frequently be alkaline, even without the addition of additional alkali thereto, due to alkalinity of the tertiary amine. However, the addition of small amounts of alkali to react with the hydrogen chloride producted by partial hydrolysis of the halogenated organic acid (which takes place particularly at higher temperatures) may be necessary, to maintain a pH above 7. From to 3 Kg mol of alkali may be used for each Kg mol of an acid quatemizing agent, and from 0 to 2 Kg mol may be used for each 1 Kg mol of a salt quaternizing agent.

.However, since any alkali remaining in the finished product must be neutralised afterwards, thereby producing salts, it is preferred to use only sufficient alkali to maintain the pH of the reaction mixture in the range of from 7 to 9.

A process of reacting certain tertiary imidazoline derivatives with quaternizing agents is fully described and claimed in the Specification of our copending Application Ser. No. 210,543 now US. Pat. No. 3,738,996

Particularly preferred alkalis for use in the process of the present invention are sodium hydroxide, potassium hydroxide, and lithium hydroxide.

Examples of oxidizing agents suitable for use in the second stage of the process of the invention are hydrogen peroxide, sodium perborate, sodium persulphate, ozone, and benzoyl peroxide. The preferred oxidizing agent is hydrogen peroxide (from which the only byproduct is water).

The second stage of the process of the invention, that is the reaction of the partially quaternized mixture produced by the first stage of the process with the oxidizing agent is preferably carried out at a temperature in the range of from 20 to 90 C, most desirably at a temperature of from 40 to 60 C.

It is, in general, preferred to use a 10 to 20 percent by weight excess of the oxidizing agent over that which is theoretically required for reaction with the free tertiary amine in the partially quaternized mixture, but particularly when hydrogen peroxide is used as the oxidizing agent, a higher excess may be used since any remaining after the reaction may be destroyed simply by keeping the reaction product at an elevated temperature.

It is preferred that the pH of the partially quaternized mixture be adjusted to from 4 to 7, and for particular preference to from 5 to 6, before the oxidizing agent is added.

The reaction mixture is desirably maintained at a temperature of from 20 to 90 C until analysis shows that none of the oxidizing agent remains in the mixture.

In some cases, when the partially quaternized mixture is treated with peroxide, reddish discolourations occur. We attribute the formation of these discolourations to secondary amines present as impurities in the starting materials. When the tertiary amine is an imidazoline derivative which has been produced by reaction between a fatty acid or other suitable fatty derivative with a polyamine, such secondary amines may be present if ring closure. to form the imidazoline has not been complete. Secondary amines may also be present if some of the imidazoline derivative has broken up during the quatemization process with opening of the imidazoline ring. We have also found that in the cases where the starting material contains secondary amines, and hence gives a discoloured product on reaction with the peroxide, a superior final product can be obtained if the partially quaternized mixture is submitted to acylation before it is reacted with the peroxide. Thus, it is preferred to precede the oxidation stage of the process of the present invention by an acylation step which comprises determining the percentage of secondary amine groups present in the composition, followedby reacting the composition with the appropriate amount of an acylating agent. If the starting materialhas been dried, and is present therefore in an anhydrous state, it is possible to effect acylation with acetic anhydride. Normally, however, the starting material contains some water, and it is therefore preferred to use an acid chloride such as benzoyl chloride, acetyl chloride or toluene sulphonyl chloride to effect the acylation. The acylation may be carried out by the well-known Schotten- Baumann procedure using caustic soda or other alkali to react with the hydrogen chloride liberated when the acid chloride reacts.

The ratio by weight of betaines to N-oxides in the final product can be varied essentially as desired, but generally it is preferred that it lie between 30:70 and 90:10 the lower the betaine content of the mixture, the lower the amount of electrolyte normally present in the product. However, even with a betaine content of percent, the amount of salt present can be so insignificant that it hardly raises any practical difficulties. Naturally, the starting material used in the oxidation stage of the process of this invention must be one which has been quaternized so as to contain the proportion of betaine which the final product is intended to have.

This invention naturally extends to a process in which the product obtained by reacting an imidazoline derivative with a halogen substituted aliphatic carboxylic acid or halogen substituted aliphatic sulfonic acid in accordance with the process described and claimed in our copending Application No. 210,543 now US. Pat. No. 3,738,996 is further reacted with an oxidizing agent to convert the free tertiary imidazoline derivative present therein to the corresponding N-oxide.

This invention also extends, of course, to detergent compositions consisting essentially of a quaternized tertiary amine and the corresponding amine oxide (and being substantially without any free tertiary amine content) as defined herein, both per se and when prepared by a process as described herein.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS OF THE INVENTION In order that this invention may be more easily understood, the following Examples are now given, though by way of illustration only, to show details of particularly preferred reagents, conditions and techniques of the process of this invention.

Example 1 A solution of 47.3 kg of monochloroacetic acid (0.5 kmol.) in 308.0 kg of water was placed in a retort fitted with an agitator, and was then mixed with 220.0 kg (1 kmol.) of technical dimethyllaurylamine. The mixture was agitated for 8 hours at 55 C and then for a further 2 hours at 90 C. Analysis of the solution showed that 4.7 percent of the dimethyllaurylamine had been converted to the betaine. The reaction mixture was then adjusted to pH 5 6 by addition of acetic acid, and carefully mixed with 72.0 kg (0.63 kmol.) of 30 percent hydrogen peroxide solution. Finally, the mixture was agitated at 55 C until no detectable amount of hydrogen peroxide was present. Analysis of the final product showed that over 99 percent of the dimethyllaurylamine had been converted to the ampholyte or N-oxide.

Example 2 A solution of 66.1 kg (0.7 kmol.) of monochloroacetic acid in 336.0 kg of water was placed in a retort fitted with an agitator and then mixed with 222.0 kg of technical dimethyllaurylamine. The mixture was agitated for 8 hours at 55 C and then for a further 2 hours at 90 C. Analysis of the solution showed that 69 percent of the dimethyllaurylamine had been converted to the betaine. The reaction mixture was then adjusted to a pH of 5 6 by the addition of acetic acid and carefully mixed with 40.0 kg (0.35 kmol.) of 30 percent hydrogen peroxide solution. The solution was then agitated at 55 C until no hydrogen peroxide could be detected therein. Analysis of the final product showed that more than 99 percent of the dimethyllaurylamine had been converted to the ampholyte or N-oxide.

Example 3 The reaction mixture was then adjusted to a pH of 5 6 by addition of acetic acid and carefully mixed with 45.4 kg (0.4 kmol.) of 30 percent hydrogen peroxide solution. The mixture was agitated at 55 C until it contained no detectable amount of hydrogen peroxide. Analysis of the final product showed that over 99 percent of the l-hydroxyethyl-2-undecylimidazoline had been converted to the ampholyte or N-oxide.

Example 4 A solution of 94.5 kg (1 kmol.) of monochloroacetic acid in 300 kg of water was placed in a retort fitted with an agitator, and mixed with 268 kg (1 kmol.) of lhydroxyethyl-Z-undecylimidazoline. Sufficient caustic soda was added to the mixture to maintain a constant pH of 7.0 7.5, and the mixture was left to agitate at 55 C. At intervals, further caustic soda was added to ensure that a pH of 7.0 7.5 was maintained in the reaction mixture.

After 24 hours, the remaining caustic soda was added; the total amount of caustic soda should amount to 40 kg (lkmol.).

Thereafter, the mixture was again left to agitate until it attained a constant pH of 8.0 8.4 (the pH measurements were carried out electrometrically in 10 percent solution).

Analysis of the aqueous solution showed that 76 percent of the l-hydroxyethyI-Z-undecylimidazoline had been converted to the betaine. The reaction mixture was adjusted to pH 5 6 by the addition of acetic acid, and was then carefully mixed with 34 kg (0.3 kmol.) of 30 percent hydrogen peroxide solution. The mixture was agitated at 50 C until no more hydrogen peroxide could be detected therein, and analysis of the final product showed that more than 99 percent of the added l-hydroxyethyl-Z-undecylimidazoline had been converted to the ampholyte or N-oxide.

Example 5 A solution of 196.5 kg of sodium 2-hydroxy-3- chloropropanesulphonate in 452 kgof water was placed in a retort fitted with an agitator, and mixed with 268 kg (1 kmol.) of l-hydro'xyethyl-Z- undecylimidazoline. Sufficient caustic soda was added to maintain a constant pH of 7.0 7.5 in the reaction mixture. The mixture was left to agitate at 55 C and at intervals further caustic soda was added to ensure that a pH of 7.0 7.5 was maintained in the reaction mixture.

After 24 hours the remaining caustic soda was added; the total amount of caustic soda should amount to 20 kg (0.5 kmol.). Thereafter, the solution was again left to agitate until a constant pH value of about 8.2 was attained (the pH measurements were carried out electrometrically in 10 percent aqueous solution).

Analysis of the aqueous solution showed that 80 percent of the l-hydroxyethyl-2-undecylimidazoline had been converted to the ampholyte.

The reaction mixture was then adjusted to pH 5 6 by the addition of acetic acid and carefully mixed with 28 kg (0.25 kmol.) of 30 percent hydrogen peroxide solution. Agitation was continued at 50 C until no more hydrogen peroxide could be detected in the reaction mixture; analysis of the final product showed that more than 99 percent of the l-hydroxyethyl-2- undecylimidazoline had been converted to the ampholyte or N-oxide.

TEST RESULTS We illustrate the value of a preferred composition obtained by the process of the invention by the following test results. These clearly show the great superiority, as regards mildness to rabbits eyes, of the composition of the invention containing the N-oxide compared with a corresponding composition containing unquatemized tertiary amine instead of N-oxide. The products used in these tests were obtained by reacting the the mixed methyl esters of the fatty acids of coconut oil, which had been stripped of the C C fraction, with aminoethyl-ethanolamine and effecting cyclisation by a known method to yield an imidazoline derivative having the following formula:

Rcfi-N-CHLCHIOH (wherein R, is the notional alkyl radical if the mixture of C 1H3 carboxylic acids present in the coconut oil is represented by the formula R COOH). The resulting product was quatemized with monochloroacetic acid in the present of sodium hydroxide, by a known method using the reactants in the proportion of 1 Kg mol of the tertiary amines to 1 Kg mol of monochloroacetic acid. The resulting product (containing both unquat ernized and quatemized tertiary amines) was treated with hydrogen peroxide by the process of this invention to convert the latter to the corresponding N-oxides. The material untreated with hydrogen peroxide, and that which had been treated with hydrogen peroxide in accordance with the process of the invention, were comparatively tested by an independent consulting laboratory to determine the effect of the compositions on rabbits eyes. The laboratory reported that the test was performed as laid down in the RDA. Handbook, Appraisal of the Safety of Chemicals in Food, Drugs, and Cosmetics 1959) p. 49 with minor modifications. For each dilution, six New Zealand White rabbits were restrained in suitable stocks. 0.1 ml of the substance under examination was instilled in one eye, the other eye remaining untreated as a control. In the case of the first three rabbits the treated eye remained unwashed. In the remaining three rabbits, the eyes were washed with 20 ml of lukewarm water 4 seconds after instillation. Inspections were made after 2, 4, 6 and 8 hours and after I, 2, 3, 4 and 7 days. The summed responses reported by the laboratory are given in the following tables; the higher the score, the more irritant the composition concerned.

(wherein R is a hydrocarbon radical which contains from 1 to 22 carbon atoms, R is a hydrocarbon radical which contains from 1 to 22 carbon atoms, R, and R contain together from 8 to 36 carbon atoms, 8 to 22 of which are present in l to 2 unbroken chains, each of which contains from 8 to 22 carbon atoms in a sequence unbroken by other non-carbon atoms, the remaining carbon atoms present, being a number selected from the group consisting of zero and integers from 1 to 28, are present in carbon chains all of which contain from 1 to 4 carbon atoms in a sequence unbroken by other non-carbon atoms; and R is an alkyl radical containing from 1 to 4 carbon atoms) is reacted with a halogenated material selected from the group consisting of halogen substituted organic acids, the so dium, potassium, lithium, magnesium, calcium, aluminium, zinc salts thereof, and mixtures thereof, said halogen substituted organic acids falling within the general SUM MED RESPONSES Unwashed Mixture of Quaternized and Mixture of Quaternized Unquaternized Tertiary Amines and Unquaternized Untreated with Hydrogen Peroxide Tertiary Amines treated with Hydrogen Peroxide 2 Hours 160 44 4 Hours I64 52 6 Hours I70 48 8 Hours 174 40 1 Day I76 2 Days 140 I0 3 Days 154 2 4 Days I74 0 7 Days I89 0 TOTAL 1501 226 Washed 2 Hours I68 36 4 Hours I44 6 Hours I 40 8 Hours I50 44 I Day I36 I6 2 Days I22 2 3 Days I32 2 4 Days I34 0 7 Days I62 0 TOTAL I298 I80 We claim:

kali-metal salts of per-acids, and ozone, to form the desired mixture of quatemized tertiary amine and amine oxide.

2. A process as in claim 1, wherein the halogenated derivative is selected from the group consisting of monochloroacetic acid, a chloropropionic acid, [3 chloropropionic acid, a bromopropionic acid, monoiodoacetic acid and a -chloro- ,6 hydroxypropionic acid, and B chloroethane sulphonic acid, 0: chloroethane sulphonic acid, ,8 bromo-ethane sulphonic acid, a hydroxy-B -chloro-ethane sulphonic acid, and the sodium and potassium salts of all these acids.

3. A process as in claim 1, wherein the oxidizing agent is selected from the group consisting of sodium perborate, sodium persulphate, and benzoyl peroxide.

4. A process as in claim 1, wherein the tertiary amine is reacted with the halogen-substituted organic acid de- 

2. A process as in claim 1, wherein the halogenated derivative is selected from the group consisting of monochloroacetic acid, Alpha - chloropropionic acid, Beta - chloRopropionic acid, Alpha - bromopropionic acid, monoiodoacetic acid and Alpha -chloro- Beta - hydroxypropionic acid, and Beta - chloroethane sulphonic acid, Alpha - chloro-ethane sulphonic acid, Beta -bromo-ethane sulphonic acid, Alpha - hydroxy- Beta -chloro-ethane sulphonic acid, and the sodium and potassium salts of all these acids.
 3. A process as in claim 1, wherein the oxidizing agent is selected from the group consisting of sodium perborate, sodium persulphate, and benzoyl peroxide.
 4. A process as in claim 1, wherein the tertiary amine is reacted with the halogen-substituted organic acid derivative in the presence of an alkali selected from the group consisting of sodium hydroxide, potassium hydroxide, and lithium hydroxide.
 5. A detergent composition of claim 1 consisting essentially of a quaternized tertiary amine and the amine oxide derived from the tertiary amine, said composition being substantially without any free tertiary amine content. 